No one was more freaked about playing Joan Rivers than her own daughter.

“I think I was more freaked out in the hair and makeup tests than I was once I got on set,” Melissa Rivers told People about portraying her late mother in Jennifer Lawrence‘s upcoming flick, “Joy.” “It was bizarre. I stopped looking in the mirror.”

After speaking with director David O. Russell and family friend-turned-producer John Davis, Rivers, 47, accepted the part.

“I thought, ‘Seriously, when am I ever going to get to work with Bradley Cooper, Jennifer Lawrence and David O. Russell?'” she said. “I was like, ‘OK, I’m in.'”

“It sounds so Pollyanna to say, but everyone from David on down could not have been lovelier or more supportive,” Rivers shared. “It didn’t hit me until I got home what a huge emotional risk I took because I don’t think any of them ever allowed me to go there. I did not want it to be an impersonation and I don’t think it came off that way.”